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The Role of the Neutral Wind in Observations of High-Latitude Ionospheric Energy Transfer
No full textJoule heating results from the collisional interaction between ions and neutrals and serves as a crucial mechanism for energy transfer between Earth\u27s magnetosphere and ionosphere-thermosphere system, particularly at high latitudes. This dissertation investigates the modulation of Joule heating by altitude-resolved neutral winds, electric fields, and conductivity variations through multi-instrument observational analysis and modeling that incorporates both in-situ and ground-based sources to measure the main drivers of ion-neutral coupling. The observations presented consistently demonstrate a dual regulatory effect of the neutral wind on energy deposition that varies systematically with both geomagnetic activity level and proximity to auroral boundaries. In regions characterized by low geomagnetic activity and poleward of auroral arcs, neutral winds enhance Joule heating and significantly contribute to ion-neutral coupling during quiescent conditions. Conversely, in regions near auroral arc boundaries or during elevated geomagnetic activity, neutral winds systematically inhibit frictional heating and function effectively as a regulator of energy deposition. Overall, the inclusion of neutral winds is shown to alter heating estimates on average by as much as 40% depending on the particular regime, which emphasizes its critical role in this energy dissipation mechanism. The altitude-dependent interactions are also investigated that both confirms previous literature while providing new insights into the nuanced role of neutral winds within this complex form of energy exchange
User Acceptance of Shared Autonomous Vehicles
Get PDFA dissertation is proposed to explore user acceptance of shared autonomous vehicles (SAVs). SAVs are facing limited user acceptance. To systematically tackle the user acceptance barriers of SAVs, the main problem can be disintegrated into two sub-problems of user acceptance of autonomous vehicles (AVs) and ridesharing. The comfort of the ride experience in AVs is a determinant of user acceptance. Understanding the influential factors and developing methodologies to quantify human comfort in AVs are essential to facilitating future research to improve human comfort in AVs. The current pooled rideshare (PR) service closely resembles the anticipated future of SAVs. Understanding why users prefer or refuse to use PR at the current stage prepares SAVs for broader acceptance in the future. Until now, a series of peer-reviewed publications have been published to achieve the technical goals. Two simulator-based user studies were conducted to instrument the research on human comfort in AVs. Statistical analysis was performed to identify the crucial vehicular behavioral factors of human comfort in AVs. The influential factors of human comfort in AVs and methodologies to quantify and detect human comfort in AVs were investigated. Two survey-based studies were deployed to facilitate the investigation of user acceptance of rideshare services. The influential factors of users\u27 willingness to consider PR were explored and identified, and the choice behaviors in ridesharing services were comprehensively modeled and analyzed. The proposed research answers a series of fundamental questions regarding the user acceptance of SAVs. For the branch of user acceptance of AVs, the research generated guidelines for improving passenger comfort in AVs by identifying a series of autonomous driving factors of passenger comfort. The research also provides fundamental tools to estimate human comfort levels for future research and in-AV applications. For the branch of user acceptance of PR, the research provided user acceptance-aware vehicle, service, and policy design insights that can promote the usage of PR
Impact of Shear Flow on Marine Biofilms Using Hyperspectral Imaging
Get PDFVarious microbial communities in marine biofilms cause biofouling on submerged surfaces, posing challenges to marine industries. Despite their ecological and economic importance, biofilms\u27 biomechanical and biochemical responses to hydrodynamic shear stress are insufficiently understood, particularly in dynamic flow conditions. To fill this gap, our study uses an innovative fiber-optic hyperspectral imaging (HSI) system and a supercontinuum laser source to examine marine biofilms\u27 structure, composition, and detachment behavior at different shear stress levels.
To detect spectral and spatial heterogeneity in live biofilms without labeling, we created a custom imaging pipeline that captures reflectance spectra in the 600-850 nm range, targeting microbial pigments and extracellular polymeric substances. We used baseline spectral mapping, supervised machine learning for bacterial strain classification, and real-time imaging in a controlled flow chamber to observe morphological transitions and pigment redistribution in laminar, low-turbulent, and high-turbulent shear conditions.
Results show biofilms under high-shear stress increase density and viscosity, while low-shear conditions promote mound-shaped microcolonies. Two-strain biofilms had more substantial spectral shifts than single-strain systems, indicating enhanced mechano-chemical responses from interspecies interactions.
This study advances hyperspectral imaging in marine microbiology by enabling stain-free, high-resolution biofilm spectral mapping under dynamic flow conditions. Understanding shear conditions for structural alteration and detachment can inform antifouling strategies for marine engineering, biomedical device sterilization, and industrial pipeline management. This research could expand to include environmental variables like temperature and nutrient gradients to create predictive models of biofilm resilience
Commodification and Objectification of the Black Male Athlete In the NFL
Get PDFThe black male body has often been viewed as a commodity in Western culture since the commodification of the black male body in the historical slave auction. Albeit slave owning ended in 1863 with the Emancipation Proclamation, it was not until 1946 that the National Football League (NFL) became integrated, and the commodification of black bodies became prevalent once again. As such, this study looks to understand how the X population from the data set for this study demonstrates the commodification of the black male body, the general discourse around the black and white male athletes, and explores the language of X users around the discourse of fantasy football to see if fans discuss black athletes as commodities as influenced by the ownership they have in fantasy football. 2272 posts were scraped using Sprinklr, and a thematic analysis revealed 15 categories and seven themes. The themes 1) dehumanization, 2) racial double standard in activism, 3) interracial dating and perceived loyalty, 4) racial stereotyping and anti-black narratives, 5) quarterback and leadership bias, 6) perceived marginalization and victimhood, and 7) objectification, revealing that the X users from the data set see black male athletes as commodities and objects. Future directions and practical implications are forwarded
An Examination of the Lived Experiences of Black Women Instructional Coaches (k-12)
No full textThe underrepresentation of Black women notably impacts the landscape of educational leadership as a result of a predominantly White workforce within the teaching profession (N. N. Johnson & Fournillier, 2021). This inequity not only highlights systemic inefficiencies as evidenced by worsening educational experiences for African American students following Brown v. BOE but also underscores the silence within studies exploring the experiences of Black women faculty in instructional leadership roles (Brown, 2005; Foster, 2005; N. N. Johnson, 2024; N. N. Johnson & Fournillier, 2021). The role of instructional coaches in shaping teacher practice positions them as integral to instructional leadership; it is critical to illuminate and understand Black women’s barriers in this field. Hermeneutic phenomenology as a methodology in this study serves two primary purposes. First, provide intentional space for exploring the lived experiences of Black women’s instructional coaches (BWICs) and utilize Black Feminist Thought (BFT) to interpret their experiences. Second, hermeneutic phenomenology offers a framework for delving into the challenges these instructional coaches encounter and how they navigate them.
As a result, the findings reveal that BWICs challenge negative stereotypes and serve as instructional leaders and advocates while confronting deficit mindsets among their colleagues. BWICs implement strategies to establish themselves as intellectual contributors in their roles while navigating resistance. This study contributes to the literature by centering the voices of Black women instructional coaches, identifying the challenges they encountered, and proposing recommendations to improve representation and visibility within instructional leadership
From awareness to action: Caregivers’ roles in multilingual learners’ literacy development
Get PDFThis design-based research study, grounded in the theoretical framework of dual capacity building, explored the impact of a literacy course on multilingual learners’ caregivers, focusing on their knowledge and self-efficacy in supporting their children’s literacy development. Findings revealed a collaborative process between caregivers and researchers, where caregivers contributed insights into their learning needs and influenced the course’s development and implementation. At the end of the course, caregivers’ average self-efficacy score showed a statistically significant 21% increase, while their knowledge ratings increased by 15%. Beyond academic support, the course significantly increased caregivers’ confidence in navigating school systems, understanding school procedures, and advocating for their children. The article closes with implications for designing effective caregiver initiatives that consider the demographics, linguistic backgrounds, and cultural complexity of multilingual learners’ caregivers and their engagement in promoting literacy at home
Foundational Robotics
No full textThis textbook is a product of Co-DREAM OER (Collaborative Development of Robotics, Mechatronics, and Advanced Manufacturing Open Educational Resources), a US Department of Education-funded initiative to develop Open Educational Resource textbooks on robotics, mechatronics, and advanced manufacturing processes. It has been created by a diverse team of scholars and graduate students from across the country and is intended for higher-level robotics courses offered by 4-year undergraduate programs.https://open.clemson.edu/robotics/1000/thumbnail.jp
